All the links for replacing the 1st generation thermostat refer to the S model. I have a small leak at the gasket of my R50 and want to know if there is a way to replace the gasket and thermostat without taking out the air box and battery box.

 

I just did this job last weekend on a non S and I would say you definitely need to take out the air box. In order to do that you have to take out the battery box. Odds are you won't be able to get the 3 bolts out that hold the battery box in. The nuts on the underside are integrated into the bottom of the box and due to age they are3 frozen on the bolts and will spin. I had to drill 2 of mine out. It takes longer to remove the air box and battery box than it does to replace the thermostat. I would recommend replacing the thermostat housing while your in there because they are prone to cracking and it is not expensive. I use pelicanparts.com for my parts.

 

Sorry but you need to pull the battery box to do it. Not a hard job but takes a few minutes.

We keep the thermostats in stock if you need one, and the thermostat housing too.

 

Thanks for the quick replies. I hope that since I live in a warm dry climate the battery box bolts may be easier to get out. I'll get the housing as well as the thermostat and post how it goes.

 

Did you drain the radiator or just drain what was in the housing?

 

The coolant in this one was fairly new, so I just let drain what was in the housing and what drained from the hoses when I disconnected them. At the time I had the front on jack stands so only lost about a half quart of coolant. If your due for a coolant change/flush then you could drain the radiator and go from there.

 

Its much easier with the battery box out to access the side of the head, in addition to the intake box. Three bolts 10mm at the bottom of the battery box can be a pain if they are stuck or rusted to the bottom, reach under and spray them if you can. Just be careful with the battery and unplugging the ecu module in the battery box.

Battery box :



Intake air box ( Square or trianguler one ) dependent on transmission





Then the thermostat and housing on the side of the engine: #10 and #12



Thermostat Housing W/ Cap 11537829959

http://www.ecstuning.com/Search/SiteSearch/11537829959/




Bolt - Priced Each

http://www.ecstuning.com/Search/SiteSearch/07131486714/ x 3



And finally

Thermostat W/ Gasket 11537596787

http://www.ecstuning.com/Search/SiteSearch/ES514854__ES2018337__ES2724023/




Here is the MINI coolant, just mix 50/50 and you are good to go.

MINI Antifreeze / Coolant - 1 Gallon ( 3.79L ) 82140031133

http://www.ecstuning.com/Search/SiteSearch/82140031133/ES196253/



Thanks

 

I have removed two 2002 battery boxes in the last month, one I had to drill out all three bolts to get it out. The other one only had one bolt with a nut underneath holding it in. It is very tight trying to get underneath to the nuts and hard to spray PB Blaster as well. The plugs for the ECU have a slide lock. You slide the lock outward on both plugs and then lift the plugs out of the ECU. Then the ECU will just pull out of the battery box.

 

Installed a new thermostat and thermostat housing on my 2003 R50 yesterday. The battery box bolts were very easy to remove which I assume is due to living in southern California and keeping the car in the garage as well. The ECU plugs are far easier to remove if the two plastic locking tabs at each end of the ECU are released to allow the ECU to be pulled upwards just enough to be able to slide the plug locks outwards without interference. And, not noted, there is a 10mm bolt at the front of the outside of the battery case that also has to be removed in addition to the three bolts inside the case. Not a difficult job but quite time consuming if you've never done it before.

 

ghass - glad you were able to get it done. Hope the diagrams helped.

 

It's rewarding performing your own service when you can and getting to know your MINI.

I ordered a thermostat housing from ECS for our 2010 R55 last week. Totally different animal. I like the support ECS provides on the forums, so decided to buy from them.

 

grussell - Thank you, mean allot.